From: Dave Young <dyoung@redhat.com>
To: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Ard Biesheuvel <ardb@kernel.org>, Borislav Petkov <bp@alien8.de>,
Sergey Shatunov <me@prok.pw>,
hpa@zytor.com,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
mingo@redhat.com, Thomas Gleixner <tglx@linutronix.de>,
x86@kernel.org, linux-efi <linux-efi@vger.kernel.org>,
initramfs@vger.kernel.org,
Donovan Tremura <neurognostic@protonmail.ch>,
Harald Hoyer <harald@hoyer.xyz>
Subject: Re: [PATCH 1/2] efi/x86: Move efi stub globals from .bss to .data
Date: Wed, 8 Apr 2020 15:43:34 +0800 [thread overview]
Message-ID: <20200408074334.GA21886@dhcp-128-65.nay.redhat.com> (raw)
In-Reply-To: <20200406180614.429454-1-nivedita@alum.mit.edu>
On 04/06/20 at 02:06pm, Arvind Sankar wrote:
> Commit
>
> 3ee372ccce4d ("x86/boot/compressed/64: Remove .bss/.pgtable from
> bzImage")
>
> removed the .bss section from the bzImage.
>
> However, while a PE loader is required to zero-initialize the .bss
> section before calling the PE entry point, the EFI handover protocol
> does not currently document any requirement that .bss be initialized by
> the bootloader prior to calling the handover entry.
>
> When systemd-boot is used to boot a unified kernel image [1], the image
> is constructed by embedding the bzImage as a .linux section in a PE
> executable that contains a small stub loader from systemd together with
> additional sections and potentially an initrd. As the .bss section
> within the bzImage is no longer explicitly present as part of the file,
> it is not initialized before calling the EFI handover entry.
> Furthermore, as the size of the embedded .linux section is only the size
> of the bzImage file itself, the .bss section's memory may not even have
> been allocated.
I did not follow up the old report, maybe I missed something. But not
sure why only systemd-boot is mentioned here. I also have similar issue
with early efi failure. With these two patches applied, it works well
then.
BTW, I use Fedora 31 + Grub2
>
> In particular, this can result in efi_disable_pci_dma being true even
> when it was not specified via the command line or configuration option,
> which in turn causes crashes while booting on some systems.
>
> To avoid issues, place all EFI stub global variables into the .data
> section instead of .bss. As of this writing, only boolean flags for a
> few command line arguments and the sys_table pointer were in .bss and
> will now move into the .data section.
>
> [1] https://systemd.io/BOOT_LOADER_SPECIFICATION/#type-2-efi-unified-kernel-images
>
> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
> Reported-by: Sergey Shatunov <me@prok.pw>
> Fixes: 3ee372ccce4d ("x86/boot/compressed/64: Remove .bss/.pgtable from bzImage")
> ---
> drivers/firmware/efi/libstub/efistub.h | 2 +-
> drivers/firmware/efi/libstub/x86-stub.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
> index cc90a748bcf0..67d26949fd26 100644
> --- a/drivers/firmware/efi/libstub/efistub.h
> +++ b/drivers/firmware/efi/libstub/efistub.h
> @@ -25,7 +25,7 @@
> #define EFI_ALLOC_ALIGN EFI_PAGE_SIZE
> #endif
>
> -#ifdef CONFIG_ARM
> +#if defined(CONFIG_ARM) || defined(CONFIG_X86)
> #define __efistub_global __section(.data)
> #else
> #define __efistub_global
> diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
> index 8d3a707789de..e7af6d2eddbf 100644
> --- a/drivers/firmware/efi/libstub/x86-stub.c
> +++ b/drivers/firmware/efi/libstub/x86-stub.c
> @@ -20,7 +20,7 @@
> /* Maximum physical address for 64-bit kernel with 4-level paging */
> #define MAXMEM_X86_64_4LEVEL (1ull << 46)
>
> -static efi_system_table_t *sys_table;
> +static efi_system_table_t *sys_table __efistub_global;
> extern const bool efi_is64;
> extern u32 image_offset;
>
> --
> 2.24.1
>
Thanks
Dave
next prev parent reply other threads:[~2020-04-08 7:43 UTC|newest]
Thread overview: 115+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-09 15:02 [PATCH 1/2] x86/boot/compressed/64: Remove .bss/.pgtable from bzImage Arvind Sankar
2020-01-09 15:02 ` [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections " Arvind Sankar
2020-02-06 11:44 ` Kees Cook
2020-02-19 16:55 ` [tip: x86/boot] " tip-bot2 for Arvind Sankar
2020-02-22 5:08 ` [PATCH 2/2] " Nathan Chancellor
2020-02-22 6:55 ` Borislav Petkov
2020-02-22 7:02 ` Nathan Chancellor
2020-02-22 7:21 ` Fangrui Song
2020-02-22 7:42 ` Nathan Chancellor
2020-02-22 15:37 ` Arvind Sankar
2020-02-22 16:44 ` Arvind Sankar
2020-02-22 17:18 ` [PATCH] x86/boot/compressed: Fix compressed kernel linking with lld Arvind Sankar
2020-02-22 18:14 ` Nathan Chancellor
2020-02-22 18:58 ` Fangrui Song
2020-02-22 20:17 ` Arvind Sankar
2020-02-22 21:01 ` Fangrui Song
2020-02-22 23:33 ` Nick Desaulniers
2020-02-22 23:57 ` Arvind Sankar
2020-02-23 19:37 ` [PATCH 0/2] Stop generating .eh_frame sections Arvind Sankar
2020-02-24 4:15 ` Nathan Chancellor
2020-02-24 20:49 ` Nick Desaulniers
2020-02-24 21:53 ` Arvind Sankar
2020-02-24 22:01 ` Nick Desaulniers
2020-02-23 19:37 ` [PATCH 1/2] arch/x86: Use -fno-asynchronous-unwind-tables to suppress " Arvind Sankar
2020-02-24 20:33 ` Nick Desaulniers
2020-02-24 21:05 ` Arvind Sankar
2020-02-24 21:12 ` Fangrui Song
2020-02-24 21:17 ` Nick Desaulniers
2020-02-24 21:22 ` Nick Desaulniers
2020-02-23 19:37 ` [PATCH 2/2] arch/x86: Drop unneeded linker script discard of .eh_frame Arvind Sankar
2020-02-24 20:45 ` Nick Desaulniers
2020-02-24 21:33 ` Arvind Sankar
2020-02-24 21:58 ` Nick Desaulniers
2020-02-24 23:21 ` [PATCH v2 0/2] Stop generating .eh_frame sections Arvind Sankar
2020-02-24 23:21 ` [PATCH v2 1/2] arch/x86: Use -fno-asynchronous-unwind-tables to suppress " Arvind Sankar
2020-02-24 23:28 ` Nathan Chancellor
2020-02-24 23:30 ` Nick Desaulniers
2020-02-25 4:10 ` Kees Cook
2020-02-25 16:53 ` [tip: x86/boot] x86/*/Makefile: " tip-bot2 for Arvind Sankar
2020-02-24 23:21 ` [PATCH v2 2/2] arch/x86: Drop unneeded linker script discard of .eh_frame Arvind Sankar
2020-02-24 23:28 ` Nathan Chancellor
2020-02-24 23:33 ` Nick Desaulniers
2020-02-25 4:11 ` Kees Cook
2020-02-25 16:53 ` [tip: x86/boot] x86/vmlinux: " tip-bot2 for Arvind Sankar
2020-02-23 22:00 ` [PATCH] x86/boot/compressed: Fix compressed kernel linking with lld Kees Cook
2020-02-24 6:06 ` Fangrui Song
2020-02-22 17:29 ` [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections from bzImage Borislav Petkov
2020-02-22 17:53 ` Arvind Sankar
2020-02-22 7:42 ` Borislav Petkov
2020-02-22 16:22 ` Arvind Sankar
2020-02-22 23:20 ` Nick Desaulniers
2020-02-24 13:28 ` Michael Matz
2020-02-24 20:51 ` Nick Desaulniers
2020-02-24 21:28 ` Fangrui Song
2020-02-24 21:48 ` Arvind Sankar
2020-02-24 22:17 ` Fangrui Song
2020-02-24 22:43 ` Arvind Sankar
2020-02-24 22:50 ` Fangrui Song
2020-02-24 23:08 ` Arvind Sankar
2020-02-25 5:35 ` --orphan-handling=warn (was Re: [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections) " Kees Cook
2020-02-25 16:42 ` --orphan-handling=warn Arvind Sankar
2020-02-25 18:29 ` --orphan-handling=warn Arvind Sankar
2020-02-25 19:42 ` --orphan-handling=warn Kees Cook
2020-02-25 20:37 ` --orphan-handling=warn Nick Desaulniers
2020-02-25 22:02 ` --orphan-handling=warn Kees Cook
2020-02-26 1:56 ` --orphan-handling=warn Fangrui Song
2020-02-26 5:35 ` --orphan-handling=warn Kees Cook
2020-02-26 19:11 ` --orphan-handling=warn Kristen Carlson Accardi
2020-02-26 19:26 ` --orphan-handling=warn Nick Desaulniers
2020-02-24 11:37 ` [tip: x86/boot] x86/boot/compressed: Remove .eh_frame section from bzImage tip-bot2 for Arvind Sankar
2020-02-24 16:41 ` Arvind Sankar
2020-02-24 17:16 ` Borislav Petkov
2020-02-24 17:28 ` Arvind Sankar
2020-02-05 16:29 ` [PATCH 1/2] x86/boot/compressed/64: Remove .bss/.pgtable " Arvind Sankar
2020-02-18 18:03 ` Arvind Sankar
2020-02-19 12:09 ` Borislav Petkov
2020-02-19 17:57 ` Arvind Sankar
2020-02-19 18:22 ` Borislav Petkov
2020-02-19 19:06 ` Arvind Sankar
2020-02-06 11:18 ` Kees Cook
2020-02-19 16:55 ` [tip: x86/boot] " tip-bot2 for Arvind Sankar
2020-04-05 15:42 ` [PATCH 1/2] " Sergey Shatunov
2020-04-05 23:18 ` Arvind Sankar
2020-04-06 0:00 ` Sergey Shatunov
2020-04-06 3:51 ` Arvind Sankar
2020-04-06 7:32 ` Ard Biesheuvel
2020-04-06 8:47 ` Borislav Petkov
2020-04-06 9:11 ` Ard Biesheuvel
2020-04-06 11:20 ` Borislav Petkov
2020-04-06 13:22 ` Arvind Sankar
2020-04-06 13:29 ` Ard Biesheuvel
2020-04-06 16:01 ` Arvind Sankar
2020-04-06 16:22 ` Ard Biesheuvel
2020-04-06 16:52 ` Arvind Sankar
2020-04-06 16:59 ` Ard Biesheuvel
2020-04-06 18:06 ` [PATCH 1/2] efi/x86: Move efi stub globals from .bss to .data Arvind Sankar
2020-04-06 18:06 ` [PATCH 2/2] efi/x86: Always relocate the kernel for EFI handover entry Arvind Sankar
2020-04-14 8:20 ` [tip: efi/urgent] " tip-bot2 for Arvind Sankar
2020-04-06 18:29 ` [PATCH 1/2] efi/x86: Move efi stub globals from .bss to .data Ard Biesheuvel
2020-04-08 7:43 ` Dave Young [this message]
2020-04-08 7:49 ` Ard Biesheuvel
2020-04-09 14:39 ` Arvind Sankar
2020-04-09 14:47 ` Ard Biesheuvel
2020-04-09 16:35 ` Arvind Sankar
2020-04-10 14:47 ` Arvind Sankar
2020-04-10 15:26 ` Ard Biesheuvel
2020-04-14 14:57 ` Daniel Kiper
2020-04-10 11:26 ` Thomas Meyer
2020-04-10 14:38 ` Arvind Sankar
2020-04-11 8:50 ` Thomas Meyer
2020-04-14 8:20 ` [tip: efi/urgent] " tip-bot2 for Arvind Sankar
2020-04-06 17:21 ` [PATCH 1/2] x86/boot/compressed/64: Remove .bss/.pgtable from bzImage Borislav Petkov
2020-04-06 8:44 ` Ard Biesheuvel
2020-04-06 12:36 ` Sergey Shatunov
2020-04-06 13:20 ` Ard Biesheuvel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200408074334.GA21886@dhcp-128-65.nay.redhat.com \
--to=dyoung@redhat.com \
--cc=ardb@kernel.org \
--cc=bp@alien8.de \
--cc=harald@hoyer.xyz \
--cc=hpa@zytor.com \
--cc=initramfs@vger.kernel.org \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=me@prok.pw \
--cc=mingo@redhat.com \
--cc=neurognostic@protonmail.ch \
--cc=nivedita@alum.mit.edu \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).